1  template<typename _Tp>
       2  struct remove_reference
       3  { typedef _Tp FOO; };
       4  
       5  template<typename _Tp>
       6  void forward (typename remove_reference<_Tp>::FOO const& __t)
       7  {
       8  }
       9  
      10  template<typename _Callable>
      11  void __invoke(_Callable const & __fn)
      12  {
      13    forward<_Callable const>(__fn);
      14  }
      15  
      16  class _State_baseV2
      17  {
      18  public:
      19    void _M_set_result()
      20    {
      21      __invoke (&_State_baseV2::_M_do_set);
      22    }
      23  
      24    void _M_do_set();
      25  };
      26